On Saturday, Donald Trump was widely condemned for his response to the white supremacists who marched in Charlottesville, Virginia, where a motorist was charged with murder after plowing into a crowd of counterprotesters. The moment called for a denunciation of white supremacists, as a number of Republican senators and numerous conservative pundits would later affirm.

Instead, President Trump condemned “hatred, bigotry and violence on many sides,” and declined to issue any specific...